Renewable fuse



F. N. CONANT. 'RENEWABLE FUSE.

APEUCATION FILED JULY 26,1919.

1,422,420. Patented July 11, 1922.

UNITED -sTATEs/ PATENT OFFICE.

FRANKLIN N. CONANT, OF NEWURYORT, MASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGNMENTS, T0 THE CHASE-SHAWMUT COMPANY, A CORPORATION OF MASSA- RENEWABLE FUSE.

` Application med July 26,

To @ZZ whom. 'it may concern:

Be it known that I, F RANKLTN N. Co- NANT, a citizen of the United States, and a resident of Newburyport, in the county of Essex and State of Massachusetts, have invented an Improvement in Renewable Fuses, of which the following is a specification.

In Aanother application #203,325, filed Nov. 22, 1917, a renewable enclosed 'fuse the cartridge type is shown having improved means for holding the terminal portion of a fuse strip.'

A desirable feature of a fuse of this type is the fact that it can be assembledand disassembled by the thumb and fingers, with out the employment of tools, and the 'fuse of said application has this capability.

It comprises lthree essential elements, a ferruled insulating fuse casing, having an integral fuse strip support, a .removable fuse-strip` engaging element or pressure plate and an end cap.

The. present invention has for its object the provision ot means for providing the removable fuse-strip pressure plate and element with which itis associated with suitable engaging means whereby said pressure plate is held inplace on the casing while the parts are being assembled and thus the chance that the plate ymay slip to the floor` and roll out of reach is avoided. As the success of a refillable fuse depends to a large extent upon the ease of assembling this point is important. The loss of the pressure plate may cause serious delay.

Fig. 1 is a side elevation and partial longi tudinal'vertical section of an electric fuse embodying my invention.

Fig. 2 is a longitudinal vertical section taken on the dotted liney 2 2, Fig. 1.

Fig. 3 is an end view of the casing.

Figs. 4 and 5, respectively, are front and side views of the fuse-strip engaging element or pressure plate.

Fig. 6 is a transverse section taken on the dotted line 6 6, Fig. 2.

Fig. 7 is a longitudinal section of the easing and fuse-strip arranged therein.

As here shown 1 represents the usual insulating cartridge tube or fuse casing andv 2 the metal ferrule embracing the end portion thereof and secured thereto by a pin 3 in the usual way or in any other desirable manner whereby said parts are relatively Specification of Letters Patent.

Patented July 11, 1.922.

1919. Serial No. 313,580.

fixed, and herein termed the :ferruled non conducting casing.

The yferrule is externally screw threaded to receive upon it the internally screw threaded end cap 11, as will hereinafter be described.

Said ferrule hasfixedly connected with it a fuse link support, which, as'here shown, consists ofan end wall et extended over the tubular bore ot the casing having an aper l ture l() through it which is made quite large to admit of Vthe product snotf combustion and other refuse material being removed from the casing after a fuse-strip has been ruptured.

This clean out7 aperture 10 has a curved side 15 made concentric with the cylindrical wall of the casing and approximately in the same plane to avoid the formation ot any obstruction at the outlet, and it has a straight side 16 arranged substantially diametrica-lly ot' the casing which is made 'as long as or longer' than the width of the fuse-strip, to

serve as a support for said strip.

Adjoining said straight side 'or 'edge the end wall is made ilat to provide a flat contact face of large area. y

The end portion of a fiat fuse-strip 17 is extended through the aperture 10 and bent over the supporting straight side 16 and laid over upon the flat contact tace of the endwall.

This form otfuse link and support therefor is merely illustrative of one embodiment of my invention. s v

As a means to engagethe. end portion ot the fuse link by a direct thrust as contrasted with a twisting motion I employ a non-rotatableelementor pressure plate here shown las a disc .7 of a diameter approximately equalling the diameter of the end of the terrule, which has a flat contact tace adapted to be arranged next the end wall. with the end portion of the fuse-strip between them, and preferably a projection 9 adapted to enter the aperture 10, said projection having an inclined portion giving it al wedge-like formation, which if4 coextensive with the straight side of the aperture thereby to engage the strip on said side support and hold it firmly.

This plate so far describedis a loose eleto repose there while the end cap ll screwed on.

Said cap ll consists of an internal screwthreaded member adaptedto engage r-vith the externally threaded ferrule and is designed to enclose 'theI plate E and subsequently 'to engage said plate 7 and thrust it down against the end of the casing by a. direct thrust.

Engaging means are provided for con necting the plate 7 with the casing, as for j instance, there may be a tongue`2() on one of said elements, as on the plate, and 'there may be an aperture 2l provided on the other element as the ferruled casing to receive said tongue, and there may be projections 22, 23, provided on the plate for engaging the casing.

As here shown the tongue 2() is formed on the front edge of the project-ion 9, and said projection is formed as a lip which is struck up from the disc, and the projections 22, 23, are extended inward respectively towards each other at the outer side of the aperture formed by striking up said projection and tongue and overlying the 0nd of the ferrule.

The aperture 2l is formed in the side wall of the ferruled casing at or about the middle of the circular side of the aperture 10, a short distance inward Afrom the end and when so disposed it will be noted that the tongue 20 enters the aperture 2l when the projection 9 enters the aperture 10.

. A loose t only is required to keep the plate 7 from slipping off the end of the i casing While the end cap is being applied and this structure enables this result to b'e accomplished.

This construction admits of the platc.7 being removed easily and quickly and also to connect it with the other parts, whereby it may be easily and quickly disassembled and may be subsequently assembled without the employment of a screw driver or other tool; and the device may be easily and quickly cleaned out and a new fuse-link supplied and perfect contacts assured.

If desired a finely divided non-conducting material may be supplied to the tube or casing to improve 'the action of the fuse, on short circuit. n

The devicewithout the fusiblelink isa complete article of manufacture in itself and may be sold' to be supplied with any suitable link.

The device is somewhat easier to assemble if the pins 3 are placed slightly eccentric, so that' the fusible element 17 may be threaded in a straight line throughV the tube, without striking the pins, but the central arrangement of the pins is slightly preferable as amatter of construction.

l. In an enclosed electric fuse of the cartridge type, the combination of a fer- 'tridge type, the combination of a ferruled casing providedwith a iixedend wall having an aperture with a straight side, a fuse strip having its end portion extended through said aperture, and adapted to engage the straight side thereof, a removable plate having an inclined lip with a straight -side struck -up from it which enters said aperture and presses the fuse strip against the straight side thereof, and a threaded end cap which encloses said plate and applies pressure thereto to hold the fuse strip;

3'. In an enclosed electric fuse of the cartridge type, the combination of a ferruled casing provided with a fixed end wall having an aperture with a straight side and having a flat face adjoining said straight side, a fuse strip having its end portion extended through said `aperture and bent over the straight side thereof onto said flat face, a removable plate having Ya lip struck up from it which enters said aperture and presses the fuse strip against thestraight side thereof, and also against said flat face, and ya threaded end cap which encloses said plate and applies pressure thereto to hold the fusestrip.

4. In an enclosed electric fuse of the cartridge type, the combination of a ferruled casing, a fuse link sup-port at the end thereof, a fuse link'contained within said casing, a removableelement associated with said support te .apply direct pressure thereto to hold the fuse link, means detachably connecting said element with said casing to hold it while the parts are being assembled, and an end cap which encloses said element and applies pressure thereto.

5. In an enclosed electric fuse of the car tridge type, the'comb-ination of an insulating casing, a. metal ferrule and a fuse link s upport on its end, a fuse link contained within said casing, a removable element cooperating with said support and arranged to apply direct pressure thereto to hold the fuse link, means detachably connecting said element .with said casing, and an end cap which encloses said element and applies pressure thereto when screwed onto tl e ferrule.

6. In an enclosed electric fuse of the cartridge type, the combination of an. insulating casing, a metal ferrule and a fuse link support on its end, a fuse link contained within said casing, a removable element cooperating with said support and arranged to apply direct pressure thereto to hold the fuse link, means detachably connecting said element with said Casin and ferrule and an end cap enclosing said e ement which applies primu're thereto Whenvscrewed onto theferru e.

7. Ina-n enclosed electric fuse of a cartridge type, the combination of a casing,a link support'with an aperture, permanently attached thereto, afuse link having its end portion extended .through said aperture andover upon the link support, a plate for engaging said fuse link on the link supportand also for engaging said fuse link at the side of the aperture, holding means for said plate which holds said plate in place on the kcasing while assembling the parts and which ,having a projection which enterssaid aperture and-presses the fuse strip against the side thereof, means detachably connecting said plate with said casing, and a threade end capwhch encloses said plate and applies pressure thereto to hold the fuse strip.

9. In an enclosed electric fuse of the cartridge type, the combinationof a ferruled casing provided with a fixed end Wall having an aperture, afuse strip having its end portion extended throughv the aperture and Over the end wall adjacent thereto, a removable plate arranged over said end Wall having a projection vvhichenters the aperture and presses the fuse stripy against the side thereof and also against-the end wall, means detaohably connecting said plate with said -casing, and a threaded end cap which enf closes said plate and applies pressure thereto to press it intoengagement with the fuse strip.

'ridge type, the combination of a ferruled casing provided with an end Wall having an aperture, and also having an aperture in its side wall, a fuse strip having its end -portion extended through said vaperture, a

removable plate for holding the fuse strip having a tongue struck up from it for enfgagement Withthe aperture in the side wall of the casing by which to detachably connect said plate with'said .casing and hold it* casing having an apertured side Wall, a fuse 10. In an enclosed electric fuse of the carlink, fuse link'supporting means at the end of said casing including a removable element arrangedto apply pressure to hold the fuse link and means detachably connecting said element includingv a tongue which enters the aperture in the side wall of the casing.

12. In an enclosed electric fuse of the cartridge type, the combination of a ferruled casing having an apertured side Wall, and an end Wall with an aperture' having a straight side, a fuse strip having its end Aportion extended through said aperture and bent over the straight side thereof, a removable plate having a projection vyhichenters the aperture and presses the fuse strip against the straight side thereof, and having a tongue which enters the aperture in the side wall and a threaded end cap which en- `closes said plate and applies pressure thereto.

13. In an enclosed electric fuse of the cartridge type, the combination of a ferruled caslng having an apertured side wall and an end Wall with an aperture having a straight side, a fuse strip having its end portion extended through said aperture and over the straight side thereof, a removable plate having a lip struck up from it which enters the aperture, and having a tongue' which enters the aperture in the side Wall,

and a threaded end cap which encloses said plate and applies pressure thereto.

14. In an enclosed electric fuse of the cartridge type, the combination of a ferruled casing havingx an apertured side Wall and an end Wall with an aperture having a straight side, a fuse strip having its end portion extended through said aperture and bent over the straight side thereof, a vremovable plate having an inclinedglip lstruck up from it and having at the termination of said lip a tongue' adapted to enter the aperture in the side Wall anda threaded end cap which encloses said plate and applies pressure thereto.

15. In an, enclosed electric fuse of the cartridgetype, the combination of a ferruled casing having an apertured side Wall' and an end -vvall with an aperture having a` straight side, a fuse strip having` its end portion extended through said aperture and over vthe straight-side thereof, a removable plate having a projection which enters the aperture and having aplurality of projections engaging the casing to detachably connect said plate therewith and a threaded end cap which encloses said'plate and applies pressure thereto'. 4

16. In an enclosed efectric fuse of the cartridge type, the combination of a ferruled casing having an apertured side wall and an en'd Wall with an aperture having a straight side, a fuse strip having its end portion extended through said `aperture and bent over the straight side thereof, a rev movable plate having a projection which enaperture in its end-Wall and a ,tip removably received in the aperture in its side-Wall and a threaded end-cap which eneloses said plate and applies pressure thereto.

ln testimony whereof, I have signed my name to this specification in the presence of two subscribin Witnesses.

Witnesses:

ERNEST Q. PRULOZMAN, HARRY C. MOORE.

RANKLIN N. CONANT. 

